DENGUE-INDEX: 2016-2019

DENGUE-INDEX

Abstract

Dengue fever is the most rapidly spreading mosquito-transmitted viral disease in the world. It causes ca. 390 million infections and 22,000 deaths annually in >100 countries. There is currently no cure and a recently licensed vaccine does not give complete protection. Disease prevention is done by mosquito vector control. Outbreaks occur periodically in most endemic countries, but outbreak detection is not accurate or timely enough to initiate control interventions in time. Critical gaps in knowledge remain. There is an urgent need to develop cost-effective and practical tools that can reliably measure dengue transmission and predict outbreaks. The project will assess human exposure to mosquito bites by detecting antibodies to mosquito saliva in human blood samples and detect dengue virus in mosquito adults and pupae. The project will be done during 2016-2019 in northeastern Thailand. It employs an integrated approach, where Study 1 is a prospective hospital-based case-control study (yr 1) to evaluate indices and dengue risk factors in positive and negative households. Study 2 is a cluster randomized controlled trial (yr 2-3) applying these indices to assess the effect of a vector control intervention consisting of treating household containers with a pyriproxyfen-spinosad mixture on epidemiological and entomological outcomes. The anticipated results will help authorities to forecast epidemics to plan and execute appropriate and timely interventions. The project is a partnership of international and national experts in the fields of entomology, virology, immunology, and epidemiology working with the Ministry of Public Health. Capacity building is an integral part of the project. As of November 2016, data on more than 100 human cases and controls in Study 1 had been collected, including blood samples, adult and immature mosquitoes, and household information. Data analysis is ongoing.

Long-term primary objective

Contribute to the development of practical early warning systems for dengue epidemics by evaluating novel entomological and immunological indices that accurately represent dengue incidence.